Euphorbia plant named ‘HJOR045’

ABSTRACT

A new distinct cultivar of  Euphorbia  plant named ‘HJOR045’, characterized by its compact plant habit; very dense and bushy plant form, mainly due to upright stems; large number of long stemmed flowers per plant due to 9 to 14 cm in length reddish peduncles; colored bracts of red, RHS 54B, with an apical margin spot of RHS 138B, green; and large, oblanceolate, yellow-green leaves with reddish-purple margins and abaxial side.

Botanical designation: Euphorbia milii Desmoul.×Euphorbia lophogona Lam.

Variety denomination: ‘HJOR045’.

BACKGROUND OF THE INVENTION

The present Invention relates to a new and distinct cultivar ofEuphorbia plant, botanically known as Euphorbia milii Desmoul.×Euphorbialophogona Lam., commonly known by the name Crown of Thorns, andhereinafter referred to by the name ‘HJOR045’.

The new Euphorbia cultivar is a product of a planned breeding programconducted by the Inventor, Steen Thomsen, in Haarslev, Fyn, Denmark. Thenew Euphorbia cultivar originated from a cross made in November of 2003by the Inventor between an unnamed, unpatented seedling plant of anEuphorbia milii Desmoul. cultivar and an unnamed, unpatented seedlingplant of an Euphorbia lophogona Lam. cultivar. The Inventor selected thenew Euphorbia cultivar as a single flowering plant from the progeny ofthe above crossing in January of 2004 on the basis of its flower colorcombination, large leaves and upright, compact plant habit. Plants ofthe new Euphorbia cultivar have upright and compact plant habit, andproduce large, abundant inflorescence with a unique color combination ofred and green.

Asexual reproduction of the new cultivar was first performed in Januaryof 2004 by terminal cuttings, and propagation in trial productionbatches in Hjortebjerg, Denmark, has demonstrated that the combinationof unique features as disclosed herein for this new Euphorbia cultivarare firmly fixed and retained through successive generations of asexualreproduction. The new cultivar reproduces true-to-type.

BRIEF SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘HJOR045’. These characteristics incombination distinguish ‘HJOR045’ as a new and distinct Euphorbiacultivar:

-   -   1. Upright, compact plant habit;    -   2. Very dense and bushy plant form, mainly due to upright stems;    -   3. Large number of long stemmed flowers per plant due to 9 to 14        cm in length reddish peduncles;    -   4. Colored bracts of red, RHS 54B, with an apical margin spot of        RHS 138B, green; and    -   5. Large, oblanceolate, yellow-green leaves, RHS 146B-D, with        reddish-purple margins and abaxial side, RHS 71B.

Plants of the new Euphorbia cultivar ‘HJOR045’ differ from plants of theparental cultivars, an unnamed, unpatented seedling plant of anEuphorbia milii Desmoul. and an unnamed, unpatented seedling plant of anEuphorbia lophogona Lam. cultivar, primarily by floral bract and leafsize and color. Plants of ‘HJOR045’ produce bright red bracts (with agreen spot) on long peduncles and large, yellow-green leaves withreddish-purple margins. In addition, plants of ‘HJOR045’ have moreproliferate flowering than the parental cultivars.

Plants of the cultivar ‘HJOR045’ can be compared to plants of theEuphorbia milii cultivar ‘Themis’ (unpatented). In side-by-sidecomparisons conducted by the Inventor in Haarslev, Denmark, plants ofthe new cultivar ‘HJOR045’ and the comparison cultivar ‘Themis’ differin the following characteristics:

-   -   1. Plants of ‘HJOR045’ are shorter and more compact than plants        of ‘Themis’;    -   2. Plants of ‘HJOR045’ have striking a color combination of red        bracts, RHS 54A to RHS 54B, orange staminate cyathia, RHS N25B,        with orange-red glands, RHS 31B, whereas plants of ‘Themis’ have        a striking color combination of red bracts, RHS 41C, staminate        cyathia with RHS 154B to RHS 154A and an edge of orange, RHS        34B;    -   3. Plants of ‘HJOR045’ have large, oblanceolate, yellow-green        colored leaves, with reddish-purple margins and undersides,        whereas plants of ‘Themis’ have dark green leaves;    -   4. Plants of ‘HJOR045’ have longer and sturdier petioles than        plants of ‘Themis’;    -   5. During the life cycle, plants of ‘HJOR045’ produce more        inflorescences and buds per plant than plants of ‘Themis’; and    -   6. Plants of ‘HJOR045’ have shorter and wider inflorescence than        the plants of ‘Themis’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying color photographs illustrate the overall appearance anddetails of flower form, color and structures of the new cultivar‘HJOR045’, showing the colors as true as it is reasonably possible toobtain in color reproductions of this type. Colors in the photographsmay differ slightly from the color values cited in the detailedbotanical description, which more accurately describe the actual colorsof the new Euphorbia cultivar.

FIG. 1 shows a side view perspective comparing a typical, pottedflowering plant of the new cultivar ‘HJOR045’ (on the left, identifiedby the Breeder's Reference 2004-5) to a typical, potted flowering plantof the comparison cultivar ‘Themis’ (on the right), both grown in 11 cmpots.

FIG. 2 shows a close-up view of young and mature floral cymes of atypical flowering plant of the new cultivar ‘HJOR045’ (identified by theBreeder's Reference 2004-5).

FIG. 3 shows a close-up view of different size leaves and thorns of atypical flowering plant of the new cultivar ‘HJOR045’ (identified by theBreeder's Reference 2004-5).

DETAILED BOTANICAL DESCRIPTION

Plants of the new cultivar ‘HJOR045’ have not been observed under allpossible environmental conditions. The phenotype may vary somewhat withvariations in environment such as temperature, light intensity, daylength, and fertility level without, however, any variance in genotype.

The aforementioned photographs, together with the followingobservations, measurements and values describe plants of the newcultivar ‘HJOR045’ as grown in a glass greenhouse in Fyn, Denmark, underconditions which closely approximate those generally used in commercialpractice. Plants of ‘HJOR045’ were grown in a greenhouse with the daytemperature range of 21° C. to 24° C. and the night temperature range of20° C. to 21° C. Plants of ‘HJOR045’ were grown in full light, and nophotoperiodic treatments or growth retardants were used. For flowerinduction, plants of ‘HJOR045’ are subjected to high irradianceconditions and a constant temperature of 24° C.

Color references are made to The Royal Horticultural Society ColourChart (R.H.S.), 4^(th) edition, except where general terms of ordinarydictionary significance are used. Plants used for this description weregrown for about 17 weeks after cutting and produced in 6 cm pots. Otherpot sizes can be used and the plants are intended for indoor use or as abedding plant in temperature climates while it is a perennial gardenplant in tropical and subtropical areas.

-   Botanical classification: Euphorbia milii Desmoul.×Euphorbia    lophogona Lam.-   Parentage:    -   -   Female or seed parent.—Unnamed, unpatented seedling plant of            Euphorbia milii Desmoul.        -   Male or pollen parent.—Unnamed, unpatented seedling plant of            Euphorbia lophogona Lam.-   Propagation:    -   -   Type cutting.—Terminal vegetative cuttings taken from plants            kept in the vegetative stage by shading and high            temperatures (25° C.).        -   Time to initiate roots.—About 10 to 14 days at 18° C. to            21° C. in tunnels in a greenhouse.        -   Root description.—Fine, fibrous, well branched.        -   Root color.—White, RHS 158B.-   Plant description:    -   -   Form.—Perennial plant with upright plant habit. ‘HJOR045’            flowers in cymes with 5 cyathia subtended by 5 glands and 2            colored bracts.        -   Crop time.—After rooting, about 16 to 18 weeks are required            to produce finished flowering plants in 11 cm pots.        -   Vigor.—Moderately vigorous growth rate.        -   Plant size.—Height (soil level to top of plant plane): About            13 cm. Width: About 16 cm.-   Lateral branches: Freely branching with about 3 lateral flowering    branches forming at every node; dense and bushy. Lateral branches    measure between 2 to 3 cm in length and about 5 mm in diameter.    Internode length measures about 6 mm. About 2 to 4 buds per lateral    stem and about 4 to 6 flowers per lateral stem. Stems are square to    pentagonal with thorned ridges — about 15 mm thick at the base.    Young stem color is yellow-green, RHS 144A, and older stems are    gray-green, RHS 194A. By each node appears a group of thorns: 1    large (16 mm) and 1 small (4 mm). Young thorns are soft and    gray-purple, RHS 187A, while the older thorns becomes stiffer and    change color to brown, RHS 187C.-   Foliage description: Leaves alternate, single, oblanceolate in    shape, entire margin (undulating when foliage young), and costate    pinnipalmate venation. Length: 11 cm. Width: About 25 mm. Apex:    Mucronate. Base: Cuneate to almost decurrent. Texture: smooth, waxy,    dull, and glabrous. Color: Young foliage: (upper side):    Yellow-green, RHS 146B, with red-purple edges, RHS 71B; (under    side): Yellow-green, RHS 146D, with red-purple edges, RHS 71B.    Mature foliage: (upper side): Yellow-green, RHS 139A; (under side):    Yellow-green, RHS 138B, with intercoastal mottling color of    red-purple, RHS 71C. Venation pattern: Costate, pinnipalmate.    Venation color: (upper side): Yellow-green, RHS 138B; (under side):    Gray-purple, RHS N187B. Petiole length: About 10 mm. Petiole    diameter: About 1 mm. Petiole color: Gray-green, RHS 195A.-   Flower description:    -   -   Flower arrangement and shape.—Floral arrangements composed            of dichasial cymes. The flowers (cyathia) are starkly            reduced so only a circle of 5 glands and the reproductive            organs are present. Subtending the cyathia are two colored            bracts. The flowers are further complicated by the unique            feature of funnel shaped floral buds appearing at the base            of the bracts in two or more layers.        -   Natural flowering season.—Continuous throughout the spring            and summer in subtropical and tropical regions. In colder            climates season, can be extended by greenhouse production            with high temperatures and supplementary irradiance.        -   Flower longevity on the plant.—About 5 to 9 weeks. However,            longevity of individual flowers is highly dependent on            temperature and light conditions. Bracts turn green with            age. Entire cymes drop after withering.        -   Rate of flower opening.—About 1 to 4 per week.        -   Fragrance.—None.        -   Inflorescence size.—Diameter: About 4×7 cm. Height: 4 to 5            cm.        -   Buds.—Funnel shape, measures about 4 mm in length and about            2 mm in diameter, color: yellow-green, RHS 150C, with            red-purple edges, RHS 63A.        -   Flowers.—Round shape, aspect of about 45° to 60°, about 2 mm            in diameter and about 1 mm in height (depth).        -   Bracts.—2, opposite, partly overlapping at base, cordate            shape with obtuse tip, average 13 mm in length and about 22            mm in width, color when opening: (upper side) red, RHS 54B;            (underside) yellow-green, RHS 150C, with red edges, RHS 54C,            color when fully opened: (upper side): red, RHS 54A, with a            green, RHS 138A, triangular spot developing at apex; (under            side) light yellow-green, RHS 150C, with red edges, RHS 54C.        -   Glands.—Flower (cyanthium) subtended by 5 conspicuous            glands. Color from orange, RHS N25B, to orange-red, RHS 31B,            during development.        -   Peduncles.—Length measuring from 9 to 14 cm, diameter            measuring about 3 mm, angle about 45°, soft in strength,            color: gray-red, from RHS 181A to RHS 181B.        -   Pedicel.—Length measuring from 1 to 4 cm, diameter measuring            about 1 mm, angle about 45°, strong in strength, color:            gray-red, RHS 181B.-   Reproductive organs:    -   -   Androecium.—Stamen: 5 (appears after flower matures).            Anthers: Globular shape measuring about 1 to 2 mm,            yellow-orange color, RHS 15A. Pollen: Plentiful,            yellow-orange color, RHS 15A.        -   Gynoecium.—Pistil: Appears before cyathia mature; one,            tripartite pistil measuring about 2 mm in length; stigma            tripartite with split ends, and color RHS 1C,            greenish-yellow; style measuring about 1 to 3 mm in length            and color, RHS 1D, greenish-yellow; ovary color, RHS 149D,            yellow-green.        -   Seeds/fruit.—None observed.-   Weather tolerance: Plants of the new Euphorbia cultivar have    exhibited good tolerance to drought, rain and wind; however,    flowering may cease during cold and dark periods when temperatures    are below +15° C.-   Pest/disease tolerance/susceptibility: Plants of the new Euphorbia    cultivar have exhibited good tolerance to following fungi: powdery    mildew and Thielaviopsis (a root rot fungus). Also, they appear to    be less infected by Thrips (Frankliniella).

1. A new and distinct cultivar of Euphorbia plant named ‘HJOR045’, asillustrated and described herein.